Suspension device



June 22 1926.

. w. TRAVELL susrausxon nzvxcz Filed March 24, 1921 2 Sheets-Sheet 1 Inveni'ar Jitorneys June 22 1926.

w. TRAVELL susransrou nzvxcz Filed March 24, 1921 2 Sheets-Sheet 2 F6. 6 r Inventar Jflorneys Patented June 22, 1926.

U NIT ED' ST A E 53'.

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WARREN TRAVELL, OF NEW YORK,- N'MY.

SUSPENSION DEVICE.

Application filed March 24, 1821. Serial No. 455,022.

\\-'l1e'nits position is changed; Ordinarily astay rope would support its outer end, to

be paid out or drawn-in as the boom novesout or in, and the-rate ofpaying out or in, relative to movement of the boom, would continuallyvary, being, different when the boom isslightly projected from what it would be with the boom out near its limit. The purpose of the present invention is to provide means for supporting the outer end of the boom at all points of its extended position without paying in or out the support, and without the load causing a: horizontal tho 1st backward alon-* the-boom. By elimina-uing such thrust, tie boom requires but little power for being moved'in and out, and for being held in any desired position, notwithstanding that its rear end may be resting on wheels or friction-reducing support oi any sort. As herein illustratechthe in vention is applied to a beam projecting and acting as an extensible boom in hoisting and transporting apparatus, in which-a carriage carrying hoisting and holding apparatus may run upon the boom out from and back to the permanent way of which the boom is an extension. It is also illustrated as applied to such a boom having a fixed hoisting sheave at the extremity of the boom; and it may with advantage be applied in various other relations, as for example, in material handling apparatus in which the boom carries a belt conveyor, or a conveyor of other type, thus providing means for conveniently estcndingor retracting the-conveyor to shift its point of operation. The objects of; the invention are accomplished by providing a .tirin support such as a towerabove the beam, onthe upper part of which are two rigidly lined points, at a-certai-n distance apart verticalr z troinwwhich extend members" that constitute a part of a system of linkage which as a whole" *aries in length, as required b'y'the Till'lfilllGllS in projection of-the hex-rm, out all of whose'elements are of unchanging length, the end of the system being depending supporting point which is capable o f moving "only in a line p'efrpenfdicuiar to the straight line between said fixed points, this depending point being the outboard point of. support for the boom. The

said linkage comprises two ties depending pivotally from the upper and'either a single or a double strut depending pivot-ally from thelowei' .oft e xe po t toget r th four links of equal len'gth, jointed together we? in a q ad l eral lrr'al'learner.t,v he

end f the strut "being io fiied is owner or the quadrilat ral and tl eflower ends of the two ties'being j inted respectively e' he We adjacent comer-sot thequadrilateral h o i gonally opposite the werfend' f the strut is said depending point, being-the point at which the boom is supported' The sides of this quadrilaielffll are illustratedas being equal'in length. It is an essential condition that the said strut shall'be equal in length to the: vertical distance between the fixed points, in order that the dependingand moving point of support shall move alwaysin alinle perpendicular to the vertical line joining Saidpoints .as said tie and said strut swing around them. Under these conditions, stresses in the link motion are determined, and a load-at the depending and moving point of support, such as weight of the boom and anything thereon, is carriel'l through the linkage to the fixed points of support without causing any thrust horizontally along the boom Whose outer end is hung atthe said moving point of support.

It follows that if the inner end of .theboom be supported, as by wheels resting on and adapted to run on a fixed way constituting an inwardextension ofthe line of the boom, a carriage and load may run on the boom and may tend .to bend the boom without the weight thereof being resolved into any thrust along t-heboom tending to move .the boom inward in the direction Of its own length. In consequence, when moving such aboom in andout, as nojstay ropjeofvarying length is used, there would only be required a sin gle driun and rope, the latter acting h'ori zontally on the boom. The rope would simply pass arounda-fixed sheave, and have t a ointo'f attachment to the boom arranged to travel .pajral-lel -withthe travel of the boom. This makes it easy to -run the ;.boom in or out, reducing the .requiredsize of ropes and motor, as co'Inpared with practice hitherto,

and in many cases permitting a hand winch to be usedan place or the motor.

If th .s insingist t a d' he d sta ce b tween the fixed points are not equal in length, the line travelled by the depending point of support will be curved, producing a varying incline of the boom; and while this may in some cases be usable it is preferable that the stated condition of equality be observed for all ordinary cases.

In previous constructions having an endwise extensible boom it has been proposed to have a stay rope or tie running from the top of the tower down to the outer end of the boom. This has to change in length as the boom moves out or in, such variations ordinarily being accomplish d by suitable attachment of the extension of the rope behind the tower, as by providing ropes and machinery for operating this stay rope and for properly varying its rate of extension or withdrawal. ,But as the depending tie which supports the outer end of the boom in the present invention does not vary in length, this invention results in another in'iportant improvement consisting in the elimination of the said ropes and machinery for operating and varying the rate of movement of the stay rope or depending tie which supports the outer end of the boom.

As the invention may be applied in various forms, the patent is not to be deemed limited to the specific forms herein set forth. It is intended that the patent shall cover. by suitable expression in the appended claims, whatever features of patentable novelty exist in the invention disclosed.

In the accompanying drawings:

Figures 1 and 2 are side elevations of an embodiment of the invention applied to a traversing hoist, respectively showing th link suspenders in positions they occupy when the boom is extended, and when partly retracted Figure 3 is a sectional view on line X-X of. Figure 2;

Figure 4-. is a side elevation showing the boom further retracted;

Figure 5 is a side elevation showing an intermediate position with a ditlerent form of boom and hoisting device; and

Figure 6 is a sectional view on line Y-Y of Figure 5.

Referring to Figures 1-8, 10 indicates fixed way of any suitable sort and 11 a boom comprising a beam projecting therefrom on which a carriage 12 may run and carry a hook and tackle 13. A traverse rope l-l passing around a sheave 15 at the outboard end of the boom provides for drawing the carriage 12 back and forth on the boom. The whole may be arranged for the carria 'e to run on both the boom and the fixed we, 10, one construction for doing which is shown inmy United States Patent No. 1,305,631, of June 3, 1919. For moving the boom in and out to desired positions of operation-,the present invention provides an weaver improvement on the device shown in said patent. The inner end of the boom may be supported in any suitable way on flanged wheels 16 running on the top of the permanent way; and the boom may be moved on said wheels by a rope attached to its rear end, as at 17, and passing around a sheave 18 at the forward extremity of the permanent way and back to a sheave and driving drum 19 and thence to the point of attachment 17, to pull the boom in or out as desired. The invention is concerned with the support for the outer end of this boom, which consists of a suspending system of linkage attached to the boom at an eye 20 herein referred to as the depending moving point of. support. The linkage which is attached to the boom at this point is supported from a tower represented in the drawings by the upriglit frame 21 which has two fixed points respectively marked 22 and 23 which may be assumed to be arranged in a vertical line braced with suftieient strength to hold the boom and its lead and the linkage which depends from said points.

From the upper point 22, two ties at and 31 extend downward to the outer ends 25 and of links 25 and 28 respectively which are two adjacent links of a quadrilateral of four links 25, 27, 28, and 29 jointed together. At the point of connection 25 of these two links 25 and 28, there is a strut 26 which rises to the lower fixed point 23 and is herein called the swinging strut. This strut may be a single member or, for symmetry and in order to obtain better distribution of stresses, it may be made double as shown in Figures 3 and 6. As represented in the drawings, the quadrilateral has its sides of equal length and all. pivotally joined together, opposite sides of the quadrilateral being parallel at all times. The lower ends of links 27 and 29, jointedly connected at the point 20, form the depending point of support at which the weight ofthe boom 1.1 is carried. The general aspect of the system of linkage, therefore. is an equilateral parallelogram the upper corner of which is connected to the lower fixed point of support by a strut or pair of struts. the outer and inner corners are connected to the upper fixed point of support by ties and the lower corner forms the de pending pointof support. The lengths of the struts 26 are equal to the vertical distance between the rigid points of support. In a system of linkage thus constructed, the point- 20 can move only in a line perpendicular to the vertical line passing through the fixed points 22 and 23, as can be demon strated math matically. Under these circumstances, any weight which is or may be suspended at the point 20 does not tend to move that point either in or out, if and when the line joining the points 22 and 23 is vertical, because the point 20 can move only in a "horizontal" path, iromWWhich it follows that any Weight imposed. thereon is perped diciilarto theiline'ot', its travel; and hasno component acting inKeither direction along itsline of travel; which is the line of movementofthe boom.

Certainloit tlie dire-rse positions which the apparatiis him assume under these eontli-l tions are illiistii'ated' in the drawings, the boom being incidentally projected tovar w ing' degrees Tlie Wheels 1 16 on which the inner end oiitheboom is supportedv in any suitable Way may, therefore, be frictionless, theoretically Without theboom tendhigto slrittits position Whena "load-is littedanv- Whereupmr it." The lii" 'g); of such a load is usiially'most conveniently effected by a hook and *tackle '13"operated from the r {ion ot-tlie stationary way, as when the boom projectsoiit over ivater. Ineuch ease, there is inevitably someisinward pressure at the sheave on"the, carriageH Q which supports the "tackle which may-be suiiieient to overcome thefri'et'ioii ofthe" wheels 16;and so for'practieal' purposes it isfdesirableto pro vide soniesort of a fastening forthe rope 17 which coht'rdls t-hmovement of the boo1n',-b1itw this iasteningneed not be very strong; and the *drmn 19"- Which controis moren'ient otthe 'boom may be relatively smalland ma'y evenbehand controlled, as

bra Winch.

As the invention-has no particular relation' to the for which the boomis applied, itis imniaterial 'What sort of hoisting: and?transportihg mechanism isemployed upon it, it any. As indicatinog this, I have shownin Figure 5 a 'ditie'renttorm 'of mec'hanisin, which is "merely'a hoistattheend of the-boom but Whieh'may be usedon the saiii'e'bi'ioin"therewith; but iawill be observed that tho-boom thus supported might beiised for any purpose such, for example, as to supporttheen'dof-a belt conveyor, or tlieend ot-a projectable plattornrhaving no inachinery.

In the claims theterm beam is used in a broad sense 3 as inclu clin r-any I such structure supported at 'eaclrendand subjectedto bending: st-r0551) the Weight thereon. It appear however, that the moving point of supportcan perform the describedfunction ot' outboard support regardless of Whether it'is associated flwithja beain And,- moreover; although the invention has thus in for clearness and conveniencebeen described as it the upper fixed-pointver Cally oa'eI thelon'er iixed point 23,

accurate represent-Mionoiteither asingle set of the suspension linkage arranged in a 17GB- tical plane or o'tadouh seteach oi which is arranged in aplaneincl'ned from the vertical as in itigure 5. Either arrangement of the sus aender link-S efi ective to support the outer endoi the boom at all points of? its horizontal travel and to eliminate rope handling and rate" controlling mechanism thereton Li claim as 'r y invention:

l. The combination, Witha bear-n inovably. srnported atone end of linkage depending; ft. a ttfiXQCl support and having a point whlchis restrained'by the linkage from 1110- tion except/in a straight line passing below 99 saidsuoport; the other'endof the beam being si aborted f saidlinlrage at said point; and ineansfothei than said linkage; to move the beam to and-fro. in the direction of its length;

QJThecolnbinatiom with a beam I11OV- ably supported at one 0nd,! of linkage de-' pending from afixed'support and' having a; po t: which is restrained by the linkage t'roin motion except ina st might line pass .ing below said support; the other end ot; the beam being); supported-by said link v atsaid poii'itythere being means applieddr rectiy to the beam and througl'r-it indirectly toithe said li lzaeje'to more the beam and iinlrag'eto and fro in the direction otthe lengflrot the beam; and the'linkage being arranged for the motion of said point to be in the direction oii'thelength of the beam. I 3. The combination with a beamsuppoited'at one endand means imparting to it niotion in the direction ot its own length; o't linkagedepending from-fixed points of support in alignment; said, linkaoe-having a point restrained by the linli'age from motion-u exceptin a line perpendicular to said aliy'iment and below both of said fixed points it support'; the other end of thebeam being: supported by said linkage at s restrained point thee-aid alignment being 1111a vertical plane perpendicular to the beam, wlierew the movement of the "beam is maintained horizontal fillCbtllQyTW ipght ot the'beam a d load carried-thereby produces-no:thrush, I inthe beam -in the direction of movement oi the beam. v

i; The combinatioin"with a beam movabiy supported at one enchand' means to more the" bEElHIQQHdWiSEfiOf adevicesupporting: the other} and, oo'mprisingtwo ties-of equal and unvarying length, a strut and a quadrilateral of links; the latter being jointed at one corner to the said beam and there supporting it, and being jointed at its opposite corner to the lower end of the strut, and being jointed to the two ties at the twocorners intervening between the two first mention-ed corners; the upper end of said strut being supported at a fixed pivot; and the two ties being suspended at a point fixed above and in a plane passing through said fixed pivot and the jointed point of support ot the beam at a distance equal to the length of the strut.

5. A horizontally extensible device for handling material, including a beam and a support for one end thereof whereon the beam is movable horizontally in the direction of its length, combined with means for thus moving the beam, and means for supporting its other end, comprising a structure rising above the first mentioned support and having two fixed points of support, both in a vertical plane perpendicular to the beam, and one of them above the other; two ties and a strut depending pivotally from them respectively, the two ties being equal and of unvarying length and the strut being equal in length to the distance between said fixed points of support; and a quadrilateral of links jointed together, the four corners of which are pivotally connected to the strut, the two ties, and the beam respectively; whereby motion of said beam is maintained horizontal in the direction of its length by the linkage.

6. A support for moving material comprising means for holding two points fixed in position, the one above the other; two ties depending pivotally from the upper point and a double strut depending pivotally from the lower point, the two ties being of equal and unvarying length and each member of the double struts being equal in length to the distance between said fixed points; and a quadrilateral of links pivotally connected, having two upper sides whose ad jacent ends are pivoted together to the lower. end of the double strut, and whose separated ends are pivoted severally to the lower ends of the two ties; and having two other sides whose upper ends are pivoted to the two ties respectively and whose lower ends, pivoted together, constitute a point of support movable in a straight line perpendicular to and below the line joining said fixed points; combined with means whereby said point of support may sustain a load; and means for transmitting force horizontally to said point of support, thereby to move it and any load sustained thereon.

7 A rectilinearly movable support, comprising, in combination, means for holding a pair of horizontal supporting axes, fixed in p it-he and p r tl e ar to the dime tion of said motion, the one above the other; two ties each composed of a pair of bars depending pivotally from the upper axis, the ties of each pair extending diverging in the general direction of said motion, and the point of support of one pair being separated at a distance from the point of support of the other pair on their common axis, with the pairs converging therefrom; two struts depending pivotally from the lower axis, their points of support being separated at a distance apart on their common axis, and these struts converging from their point of support and being of length equal to the distance between said fixed axes. when measured in projection on a vertical plane perpendicular to said fixed axes; and eight links, constituting two quadrilaterals side by side, each quadrilateral having its upper corner pivoted to one of the two strut-s, its two corners of middle height pivoted to the diverged ends of the ties in one of said pairs, and its lowest corner joined with the lowest corner of the other quadrilateral to form the point of support; whereby said point is supported in two directions against deviation from a rectilinear path.

8. The combination of a boom extensible and retractible in the direction of its own length and movably supported at its inner end; means for so extending and retracting the boom; a carriage travelling on said boom from which the load to be carried is suspended; means for moving the carriage along the boom; means for raising and lowering the load suspended from the carriage; and link suspenders depending from two fixed points of support and comprising two ties of equal and unvarying length, a strut equal in length to the distance between the said two points of support, and a quadrilateral of links having one side whose ends are pivoted to the strut and to one of the ties respectively, having a second side whose ends are pivoted to the strut and to the second tie respectively, having a third side whose ends are pivoted to one of the ties and to a point of the boom respectively, and having a fourth side whose ends are pivoted to the other tie and to said point of the boom respectively; thereby constituting a point of support for the outer end of: the boom.

9. The combination of a boom extensl'ole and retractible in the direction of its own length and movably supported at its inner end; means for so extending and retracting the boom; and a'support for the outer end of the boom comprising link suspenders depending from two fixed points of support and comprising two ties of equal and unvarying length, a strut equal in length to the distance between the said two points of support, and a quadrilateral of links having one s e Wh se e ds a Pi t 9 he t t to one of the ties respectively, having a secpoint of the boom respectively; thereby con- 03nd side Whose ends are pivoted to the strut stituting a point of support for the outer and to the second tie respectively, having it end of the boom. 10 third side Whose ends are pivoted to one of Signed at New York, New York, this the ties and to a point of the boom respec- 23rd day of March, 1921.

tively, and having a fourth side Whose ends are pivoted to the other tie and to said WARREN TRAVELL. 

